Hi there. I am viewing the topics that include "popups" that are either auto sizing or custom sized from inside RoboHelp 2015 using the "View item" function from inside the Edit ribbon.
I did notice I have all of the current RH2015 "patches" installed and I tried viewing using Google Chrome browser. Although it did not work, I did have a blue bordered box display around where each popup occurs when "viewing" using Chrome.
Viewing or previewing inside RH doesn't always represent what you're going to get once you generate - don't rely on it to get an accurate representation - do the generate function & examine the output folder outside of RH.